Technical Field
[0001] The present invention relates to a process cartridge which is detachably included
in an image forming apparatus such as a laser printer and a copy machine, a photosensitive
drum unit which is included in the process cartridge, a developing roller unit, an
end member which is attached to a columnar rotary body of the photosensitive drum
unit or the developing roller unit, a bearing member which configures the end member,
an intermediate member which is included in the bearing member, and a bearing member
body.
Background Art
[0002] An image forming apparatus such as a laser printer and a copy machine includes a
process cartridge which is provided to be attachable to and detachable from an image
forming apparatus body (hereinafter, referred to as an "apparatus body").
[0003] The process cartridge is a member which forms contents which are to be shown, such
as characters and figures, and which transfers these contents to a recording medium
such as a paper sheet. More specifically, the process cartridge includes a photosensitive
drum in which the contents to be transferred are formed. In addition, other various
units for forming the contents which are to be transferred to the photosensitive drum
are arranged together in the process cartridge. For example, these units include a
developing roller unit, a charging roller unit, and a cleaning unit.
[0004] In a case of the process cartridge, the same process cartridge is attached to or
detached from the apparatus body for maintenance purpose, or a new process cartridge
is mounted on the apparatus body after the old process cartridge is detached from
the apparatus body. Users of the image forming apparatus can carry out such attachment
and detachment work of the process cartridge by themselves. Therefore, from this point
of view, it is desirable that the attachment and detachment work be carried out as
easily as possible.
[0005] However, a drive shaft of the apparatus body is configured so as to engage with the
photosensitive drum included in the process cartridge directly or via other members.
This causes the photosensitive drum to receive a rotation force from the drive shaft
and to rotate. Therefore, in order to attach and detach the process cartridge to and
from the apparatus body, on each occasion, it is necessary to carry out disengagement
work (detachment) and re-engagement work (mounting) between the drive shaft of the
apparatus body and the photosensitive drum.
[0006] Therefore, if the photosensitive drum (process cartridge) can be attached to and
detached from the drive shaft by moving the photosensitive drum in a direction along
an axis of the drive shaft of the apparatus body, it is possible to configure a relatively
simple apparatus. However, in a viewpoint of downsizing of the image forming apparatus
and ensured space arrangement required for the attachment and detachment work of the
process cartridge, it is preferable that the process cartridge be detached from the
apparatus body so as to be pulled out in a direction different from the direction
along the axis of the drive shaft, or so as to be pushed in an opposite direction
when being attached.
[0007] Patent Literature 1 discloses a configuration in which the process cartridge is attached
to and detached from the apparatus body in the direction different from the direction
along the axis of the drive shaft of the apparatus body. Specifically, a coupling
member disclosed in Patent Literature 1 is attached to a drum flange (bearing member)
so as to be swingable by being provided with a spherical portion. Therefore, a portion
(rotation force receiving member) which is included in the coupling member and engages
with the drive shaft of the apparatus body swings around the spherical portion, and
can change an angle with respect to the axis of the photosensitive drum. This facilitates
the attachment and detachment between the drive shaft of the apparatus body and the
photosensitive drum.
[0008] In addition, according to the invention disclosed in Patent Literature 1, in a structure
for connecting a swinging shaft member to the bearing member, a groove for introducing
a rotation force transmission pin included in the shaft member to the bearing member
is disposed on an inner peripheral side of the bearing member. This groove is formed
so as to extend in a rotation direction. This groove facilitates the attachment of
the rotation force transmission pin to the bearing member.
Citation List
Patent Literature
Non Patent Literature
[0010] Non Patent Literature 1: Technical Report Publication No.
2010-502200, Japan Institute of Invention and Innovation
Summary of Invention
Technical Problem
[0011] However, according to the inventions disclosed in Patent Literature 1 and Non Patent
Literature 1, it is difficult to realize smooth attachment of the shaft member to
the bearing member, smooth swing of the shaft member, and smooth attachment and detachment
between the shaft member and the apparatus body. For example, specifically, each member
needs to have high accuracy in order to fulfill a desired function. Consequently,
uneven quality of the shaft member has a great influence on the function.
[0012] In addition, according to a structure of the coupling member and a drum flange (bearing
member) holding the coupling member which is disclosed in Patent Literature 1, there
is provided a structure in which the coupling member is swingable and the spherical
portion is directly held by the drum flange. Accordingly, it is necessary to forcibly
attach and detach the coupling member when the spherical portion is attached to the
drum flange (bearing member). Then, the forcible attachment and detachment may cause
damage to the shaft member. In this regard, there is a problem of poor workability,
and the shaft member is disadvantageously affected when in reuse.
[0013] In contrast, according to a structure disclosed in Non Patent Literature 1, when
the shaft member is swung, a tilting angle thereof is limited. Consequently, in some
cases, a sufficient swing angle cannot be obtained.
[0014] Therefore, the present invention is made in view of the above-described problems,
and an object thereof is to provide a bearing member which can transmit a rotation
force equivalent to that in the related art, which can be attached to and detached
from an apparatus body, which is smoothly operated, and which is less likely to receive
an influence from uneven quality of a shaft member. In addition, there are provided
an end member, a photosensitive drum unit, a developing roller unit, a process cartridge,
an intermediate member, and a bearing member body.
Solution to Problem
[0015] Hereinafter, the present invention will be described. Here, for ease of understanding,
reference numerals in the drawings are given in parentheses, but the present invention
is not limited thereto.
[0016] The present invention includes a bearing member (41, 141) configured to be arranged
in an end portion of a columnar rotary body (35, 524), wherein a shaft member (70)
is attachable to the bearing member, the bearing member including: a body (45, 145)
that includes a cylindrical body (46) and a holding portion (50, 150) which is arranged
inside the cylindrical body; and an intermediate member (60, 160, 260) that is held
by the holding portion of the body, wherein the holding portion includes an intermediate
member guide (51, 52, 53, 54, 151, 152) which guides the intermediate member so that
the intermediate member rotates, and the intermediate member includes a portion in
which the shaft member is arranged.
[0017] Here, the "columnar rotary body" is a general idea including a rotary body which
has a solid round bar shape and rotates around an axis line, and a rotary body which
has a cylindrical hollow shape and rotates around an axis line.
[0018] In an aspect of the bearing member (41) according to the present invention, the intermediate
member guide (51, 52, 53, 54) is a guide groove into which an outer peripheral portion
of the intermediate member is inserted, wherein the guide groove slides and guides
the outer peripheral portion, and at least a portion on a bottom surface of the guide
groove is a curved surface.
[0019] In an aspect of the bearing member (41) according to the present invention, the curved
surface on the bottom surface of the guide groove (51, 52, 53, 54) comes into contact
with the outer peripheral portion of the intermediate member (60), thereby regulating
a movement in a direction along an axis of the cylindrical body (46) of the intermediate
member.
[0020] In an aspect of the bearing member (141) according to the present invention, a protruding
guide member (165) is disposed in the intermediate member (160, 260), the intermediate
member guide (151, 152) is a guide surface on which the guide member slides, and at
least a portion of the guide surface is a curved surface.
[0021] In an aspect of the bearing member (141) according to the present invention, a guide
member insertion groove (150d, 350d) is disposed in the holding portion (150) for
causing the guide member (165) to reach the guide surface (151, 152).
[0022] In an aspect of the bearing member (141) according to the present invention, the
guide member insertion groove includes a snap-fit structure which is a portion narrower
than an outer shape of the guide member.
[0023] In an aspect of the bearing member (141) according to the present invention, a groove
(261, 262) into which a portion of a shaft member (70) is inserted is disposed in
the intermediate member (260), and the groove includes a snap-fit structure (261a,
262a) which is a portion narrower than an outer shape of the inserted portion of the
shaft member.
[0024] In an aspect of the bearing member (141) according to the present invention, the
snap-fit structure of the guide member insertion groove (150d) can be disengaged with
a force weaker than a force for the snap-fit structure (261a, 262a) of the groove
(261, 262) disposed in the intermediate member (260).
[0025] In an aspect of the bearing member (141) according to the present invention, the
snap-fit structure of the guide member insertion groove (150d) needs to be disengaged
with a force stronger than a force for the snap-fit structure (261a, 262a) of the
groove (261, 262) disposed in the intermediate member (260).
[0026] An end member (40, 140) according to the present invention includes: a shaft member
(70); and the bearing member (41, 141), wherein the shaft member includes: a rotary
shaft (85); a rotation force receiving portion (71) which is included on one end side
of the rotary shaft, which can engage with a rotation force applying portion of an
image forming apparatus body, and which receives a rotation force from a drive shaft
by maintaining an engaging posture thereof; a proximal end portion (90) which is arranged
on the other end side of the rotary shaft; and a rotation force transmission projection
(95) which projects from the proximal end portion, wherein a groove (61, 62, 161,
162, 261, 262) with which the rotation force transmission projection engages is disposed
in the intermediate member, and the shaft member is assembled to the intermediate
member by the rotation force transmission projection engaging with the groove.
[0027] A photosensitive drum unit (30) according to the present invention is configured
such that the columnar rotary body is a photosensitive drum (35), and the photosensitive
drum unit includes the photosensitive drum and the end member (40, 140) which is arranged
in at least one end portion of the photosensitive drum.
[0028] A developing roller unit (523) according to the present invention is configured such
that the columnar rotary body is a developing roller (524), and the developing roller
unit includes the developing roller and the end member (40) which is arranged in at
least one end portion of the developing roller.
[0029] A process cartridge (20) according to the present invention includes: a housing (21);
and the photosensitive drum unit (30) according to claim 11 which is held in the housing.
[0030] A process cartridge according to the present invention includes: a housing; and the
developing roller unit which is held in the housing.
[0031] An intermediate member (60, 160, 260) according to the present invention is configured
to be included in a bearing member (41, 141) which is arranged in an end portion of
a columnar rotary body (35, 524) and to which a shaft member (70) is attached, wherein
the intermediate member is configured to be arranged between a body (45, 145) of the
bearing member and the shaft member (70), the intermediate member including: a portion
in which the shaft member is arranged so as to be swingable; and a guided portion
which is guided by a portion of the body so that the intermediate member is swingable
with respect to the body.
[0032] A body (45, 145) of a bearing member according to the present invention is configured
to be included in the bearing member (41, 141) configured to be arranged in an end
portion of a columnar rotary body (35, 524) and to attach a shaft member (70) to the
bearing member, wherein the shaft member is attached to the body via an intermediate
member (60, 160, 260), the body of the bearing member including: a cylindrical body
(46); and a holding portion (50, 151) that is arranged inside the cylindrical body
and holds the intermediate member so as to be swingable, wherein the holding portion
includes an intermediate member guide (51, 52, 53, 54, 151, 152) which guides the
intermediate member so that the intermediate member rotates.
Advantageous Effects of Invention
[0033] According to the present invention, the swing in at least one direction is performed
by the rotation of the intermediate member and the body. Therefore, a smooth pivotal
movement (swing of the shaft member) is possible. In this case, the pivotal movement
(swing of the shaft member) has no relationship with a form of the shaft member. Accordingly,
even if the shaft member side has slightly uneven dimensions, it is possible to ensure
sufficiently smooth swing. In addition, the limitation of the tilting angle is relieved
when the shaft member swings. Therefore, it is possible to tilt the shaft member more
greatly.
Brief Description of Drawings
[0034]
Fig. 1 is a conceptual view of an image forming apparatus body 10 and a process cartridge
20.
Fig. 2 is a diagram schematically illustrating a structure of the process cartridge
20.
Fig. 3(a) is an external perspective view of a photosensitive drum unit 30 for describing
a first embodiment, and Fig. 3(b) is an external perspective view of an end member
40.
Fig. 4 is an exploded perspective view of a bearing member 41.
Fig. 5(a) is a plan view of a body 45 of the bearing member 41, and Fig. 5(b) is a
perspective view of the body 45 of the bearing member 41.
Fig. 6 is a cross-sectional view of the body 45 of the bearing member 41.
Fig. 7(a) is a perspective view of an intermediate member 60, Fig. 7(b) is a front
view of the intermediate member 60, and Fig. 7(c) is a cross-sectional view of the
intermediate member 60.
Fig. 8(a) is a cross-sectional view of a shaft member 70, and Fig. 8(b) is another
cross-sectional view of the shaft member 70.
Fig. 9 is an enlarged view of a coupling member 71.
Fig. 10(a) is a cross-sectional view of the end member 40, and Fig. 10(b) is another
cross-sectional view of the end member 40.
Fig. 11(a) is a view illustrating an example where the shaft member 70 has a tilted
posture on a cross section of the end member 40, and Fig. 11(b) is a view illustrating
an example where the shaft member 70 has a tilted posture on another cross section
of the end member 40.
Fig. 12(a) is a perspective view illustrating a drive shaft 11 of an image forming
apparatus body, and Fig. 12(b) is a view for describing a posture where the drive
shaft 11 is connected to a coupling member 71.
Fig. 13(a) is a view for describing a scene where a process cartridge is mounted on
an apparatus body, and Fig. 13(b) a view for describing another scene where the process
cartridge is mounted on the apparatus body.
Fig. 14 is a perspective view of an end member 140 which describes a second embodiment.
Fig. 15 is an exploded perspective view of a bearing member 141.
Fig. 16(a) is a plan view of a body 145 of the bearing member 141, and Fig. 16(b)
is a perspective view of the body 145 of the bearing member 141.
Fig. 17 is a cross-sectional view of the body 145 of the bearing member 141.
Fig. 18(a) is another cross-sectional view of the body 145 of the bearing member 141,
and Fig. 18(b) is further another cross-sectional view of the body 145 of the bearing
member 141.
Fig. 19(a) is a perspective view of an intermediate member 160, Fig. 19(b) is a front
view of the intermediate member 160, and Fig. 19(c) is a cross-sectional view of the
intermediate member 160.
Fig. 20 is a cross-sectional view of an end member 140.
Fig. 21(a) is another cross-sectional view of the end member 140, and Fig. 21(b) is
further another cross-sectional view of the end member 140.
Fig. 22 is a view illustrating an example where the shaft member 70 has a tilted posture
on a cross section of the end member 140.
Fig. 23(a) is a view illustrating an example where the shaft member 70 has a tilted
posture on another cross section of the end member 140, and Fig. 23(b) is a view illustrating
an example where the shaft member 70 has a tilted posture on further another cross
section of the end member 140.
Fig. 24(a) is a perspective view of an intermediate member 260, Fig. 24(b) is a front
view of the intermediate member 260, and Fig. 24(c) is a plan view of the intermediate
member 260.
Fig. 25(a) is a perspective view of a posture where the shaft member 70 is attached
to the intermediate member 260, and Fig. 25(b) is a cross-sectional view of the posture
where the shaft member 70 is attached to the intermediate member 260.
Fig. 26(a) is a plan view of a body 345 of a bearing member 341, and Fig. 26(b) is
a perspective view of the body 345 of the bearing member 341.
Fig. 27 is a cross-sectional view of the body 345 of the bearing member 341.
Fig. 28(a) is another cross-sectional view of the body 345 of the bearing member 341,
and Fig. 28(b) is further another cross-sectional view of the body 345 of the bearing
member 341.
Fig. 29 is a perspective view of the bearing member 341.
Fig. 30(a) is a cross-sectional view of the bearing member 341, and Fig. 30(b) is
another cross-sectional view of the bearing member 341.
Fig. 31 is a view for describing a scene where the intermediate member 160 is attached
to the body 345.
Fig. 32 is a view for describing tilting of the shaft member 70 and a position of
a guide member 165.
Fig. 33(a) is a perspective view of a bearing member 341', and Fig. 33(b) is a perspective
view illustrating an enlarged portion of the bearing member 341'.
Fig. 34 is a perspective view of the bearing member 341".
Fig. 35(a) is a cross-sectional view of a body 445, and Fig. 35(b) is another cross-sectional
view of the body 445.
Fig. 36(a) is a perspective view of an intermediate member 460, Fig. 36(b) is a front
view of the intermediate member 460, and Fig. 36(c) is a plan view of the intermediate
member 460.
Fig. 37(a) is a view for describing a scene where the intermediate member 460 is attached
to the body 445, and Fig. 37(b) is a view for describing a scene where the intermediate
member 460 swings inside the body 445.
Fig. 38 is a view for describing a form where the end member 40 is included in a developing
roller unit 523.
Description of Embodiments
[0035] Hereinafter, the present invention will be described with reference to embodiments
illustrated in the drawings. However, the present invention is not limited to the
embodiments. In addition, for ease of description, each drawing illustrates members
by omitting or seeing through some members if necessary, or by using an exaggerated
shape. In some cases, hatching is given on a surface serving as an end surface in
cross-sectional views.
[0036] Fig. 1 is a diagram for describing a first embodiment, and is a perspective view
schematically illustrating a process cartridge 20 which includes an end member 40
(refer to Fig. 2), and an image forming apparatus body 10 which is used by mounting
the process cartridge 20 thereon (hereinafter, referred to as an "apparatus body 10").
As illustrated in Fig. 1, the process cartridge 20 can be mounted on the apparatus
body 10 by being moved in a direction illustrated by arrow A in Fig. 1, and can be
detached from the apparatus body 10. The direction of (A) is a direction different
from an axial direction of a drive shaft of the apparatus body 10. The apparatus body
10 and the process cartridge 20 configure an image forming apparatus. Hereinafter,
detailed description will follow.
[0037] Fig. 2 schematically illustrates a structure of the process cartridge 20. As is understood
from Fig. 2, the process cartridge 20 is configured so that an inner side of a housing
21 internally accommodates a photosensitive drum unit 30 (refer to Fig. 3), a charging
roller unit 22, a developing roller unit 23, a regulating member 24, and a cleaning
blade 25. In a posture where the process cartridge 20 is mounted on the apparatus
body 10, a recording medium such as a paper sheet is moved along a line illustrated
by II in Fig. 2. In this manner, an image is transferred onto the recording medium
from the photosensitive drum unit 30.
[0038] In addition, attachment and detachment of the process cartridge 20 to and from the
apparatus body 10 are performed roughly as follows. In the present embodiment, the
photosensitive drum unit 30 included in the process cartridge 20 is rotated by receiving
a rotation driving force from the apparatus body 10. Therefore, at least when operated,
a drive shaft 11 (refer to Fig. 12(a)) of the apparatus body 10 and an end member
40 (refer to Fig. 3(b)) of the photosensitive drum unit 30 engage with each other.
In this manner, the photosensitive drum unit 30 is in a state where the rotation force
can be transmitted (refer to Fig. 12(b)).
[0039] In contrast, when the process cartridge 20 is attached to or detached from the apparatus
body 10, the drive shaft 11 and the end member 40 need to quickly engage with each
other or disengage from each other so as not to inhibit mutual movement to the other
side or mutual rotation regardless of their postures.
[0040] In this manner, the end member 40 of the photosensitive drum unit 30 properly engages
with the drive shaft 11 of the apparatus body 10, thereby transmitting the rotation
driving force.
[0041] Hereinafter, each configuration will be described.
[0042] As is understood from Fig. 2, the process cartridge 20 includes the charging roller
unit 22, the developing roller unit 23, the regulating member 24, the cleaning blade
25, and the photosensitive drum unit 30. These elements are internally accommodated
inside the housing 21. The respective elements are configured as follows.
[0043] The charging roller unit 22 charges a photosensitive drum 35 (refer to Fig. 3) of
the photosensitive drum unit 30 by using a voltage applied from the apparatus body
10. The charging roller unit 22 is rotated to follow the photosensitive drum 35, and
comes into contact with an outer peripheral surface of the photosensitive drum 35,
thereby performing this charging.
[0044] The developing roller unit 23 is a member including a roller for supplying a developer
to the photosensitive drum 35. Then, an electrostatic latent image formed in the photosensitive
drum 35 is developed by the developing roller unit 23. A fixed magnet is embedded
in the developing roller unit 23.
[0045] The regulating member 24 is a member which adjusts an amount of the developer adhering
to an outer peripheral surface of the developing roller unit 23 and applies a frictional
electrostatic charge to the developer itself.
[0046] The cleaning blade 25 is a blade which removes the developer remaining after the
transfer by coming into contact with the outer peripheral surface of the photosensitive
drum 35 and by using a distal end thereof.
[0047] The photosensitive drum unit 30 is a member whose surface has characters or figures
which are to be transferred to a recording medium such as a paper sheet. Fig. 3(a)
illustrates an external perspective view of the photosensitive drum unit 30. As is
understood from Fig. 3(a), the photosensitive drum unit 30 includes the photosensitive
drum 35, a lid member 36, and the end member 40. Fig. 3(b) illustrates a perspective
view focusing on the end member 40. Hereinafter, the photosensitive drum unit 30 will
be described with reference to Figs. 2(a) and 2(b) and appropriate drawings.
[0048] The photosensitive drum 35 is a member in which an outer peripheral surface of a
drum cylinder (sometimes referred to as a "substrate") serving as a columnar rotary
body is coated with a photosensitive layer. That is, the drum cylinder is a conductive
cylinder made of aluminum, and is configured so that the cylinder is coated with the
photosensitive layer. As will be described later, the end member 40 is attached to
one end of the photosensitive drum 35, and the lid member 36 is arranged in the other
end. In the present embodiment, the drum cylinder is configured to have a cylindrical
hollow shape, but may be configured to have a solid round bar shape. However, at least
the lid member 36 and the end member 40 are formed so as to be properly attached to
an end portion thereof.
[0049] The lid member 36 is a member formed of a resin, in which a fitting portion fitted
to an inside of a cylinder of the photosensitive drum 35 and a bearing portion arranged
to cover one end surface of the photosensitive drum 35 are formed coaxially. The bearing
portion has a disk shape covering the end surface of the photosensitive drum 35, and
includes a portion for receiving a shaft disposed inside the process cartridge. In
addition, a ground plate formed of a conductive material is arranged in the lid member
36, thereby electrically connecting the photosensitive drum 35 and the apparatus body
10 to each other.
[0050] Without being limited to this lid member described as an example of the present embodiment,
other types of lid members which are generally available can also be adopted. For
example, a gear for transmitting the rotation force may be arranged in the lid member.
In addition, the above-described conductive material may be disposed on the end member
40 side (to be described later).
[0051] The end member 40 is a member attached to an end portion opposite to the above-described
lid member 36 within an end portion of the photosensitive drum 35, and includes a
bearing member 41 and a shaft member 70.
[0052] The bearing member 41 is a member which is fixed to the end portion of the photosensitive
drum 35. Fig. 4 illustrates an exploded perspective view of the bearing member 41.
As is understood from Fig. 4, the bearing member 41 includes a body 45 and an intermediate
member 60. Each of these will be described.
[0053] Fig. 5(a) illustrates a view when the body 45 is viewed from a side to which the
intermediate member 60 is inserted, and Fig. 5(b) illustrates a view when the body
45 is viewed from a different angle from that in Fig. 3, respectively. In addition,
Fig. 6 illustrates a cross-sectional view taken in an axial direction along a line
illustrated by VI-VI in Figs. 4, 5(a), and 5(b). In the body 45 according to the present
embodiment, a cross section in the axial direction along a line (line illustrated
by VI'-VI' in Fig. 5(a)) in which the line illustrated by VI-VI is rotated by 90°
around the axis of the body 45 is the same as that in Fig. 6.
[0054] In the present embodiment, the body 45 includes a cylindrical body 46 having a cylindrical
shape as is understood in Figs. 3 to 6. In addition, an outer peripheral surface of
the cylindrical body 46 has a ring-shaped contact wall 47 erected along the outer
peripheral surface, and a gear 48. An outer diameter of the cylindrical body 46 is
substantially the same as an inner diameter of the above-described photosensitive
drum 35. One end side of the cylindrical body 46 is inserted into and fitted to the
photosensitive drum 35, thereby fixing the body 45 to the photosensitive drum 35.
In this case, the cylindrical body 46 is inserted to a depth which allows the end
surface of the photosensitive drum 35 to come into contact with the contact wall 47.
In this case, an adhesive may be used for more strengthened fixing. In addition, a
groove 46a or concave and convex portions may be disposed in the cylindrical body
46 of a portion in which the adhesive is arranged. This causes the adhesive to be
held in the groove 46a or the concave portion, thereby further strengthening adhesion
between the photosensitive drum 35 and the body 45.
[0055] The gear 48 is a gear for transmitting the rotation force to the developing roller
unit 23, and is a helical gear in the present embodiment. Without being particularly
limited thereto, a type of the gear may be a spur gear. However, the gear may not
be necessarily disposed.
[0056] A plate-shaped bottom portion 49 is disposed on a cylindrical inner side of the cylindrical
body 46 so as to close at least a portion of the inner side of the cylindrical body
46. Furthermore, within the inner side of the cylindrical body 46 which is partitioned
by the bottom portion 49, a holding portion 50 is disposed on an inner side opposite
to a side which is fixed to the photosensitive drum 35.
[0057] Here, an example including the bottom portion 49 has been described, but the bottom
portion 49 may not be necessarily disposed. As will be described later, the shaft
member 70 and the intermediate member 60 can be held by the holding portion 50. Accordingly,
without disposing the bottom portion 49, it is possible to hold the shaft member 70
and the intermediate member 60 inside the cylindrical body 46.
[0058] The holding portion 50 forms guide grooves 51, 52, 53, and 54 which serve as an intermediate
member guide, inside the cylindrical body 46. Therefore, in the holding portion 50,
multiple projections 50a are arranged at predetermined gaps along an inner peripheral
surface of the cylindrical body 46 so as to project from an inner surface of the cylindrical
body 46 toward the axis of the cylindrical body 46. The gaps between the adjacent
projections 50a form the guide grooves 51, 52, 53, and 54. In addition, a space (concave
portion) is formed in the axis portion surrounded by the projections 50a, and a proximal
end portion (spherical body 90, refer to Fig. 8) of the shaft member 70 is arranged
therein as described herein.
[0059] Here, in the guide grooves, two guide grooves opposing each other across the axis
of the cylindrical body 46 function as a pair. Then, the guide groove may actually
be used as one pair as will be described later. However, as in the present embodiment,
four guide grooves 51, 52, 53, and 54, that is, two pairs may be disposed. Furthermore,
six (three pairs) or more guide grooves may be disposed. This can improve the balance
of material behavior (sink mark) when the body 45 is injection-molded, and can manufacture
a more accurate body. Therefore, the number of guide grooves may be determined in
terms of the material behavior.
[0060] Herein, a pair of guide grooves configured to have the guide grooves 51 and 52 whose
cross-sections are illustrated in Fig. 6 will be described. Another pair of guide
grooves configured to have the guide grooves 53 and 54 is the same as the above-described
pair, and thus, description thereof will be omitted.
[0061] As described above, the guide groove 51 is a groove which extends along a direction
of the axis (illustrated by line O in Fig. 6) of the cylindrical body 46 formed on
an inner peripheral surface of the cylindrical body 46. Then, the guide groove 51
is configured so that the axis O side of the cylindrical body 46 is open, and has
a bottom surface on an inner peripheral surface side of the cylindrical body 46. In
contrast, the guide groove 52 is a groove disposed so as to oppose the guide groove
51 on the opposite side across the axis O of the cylindrical body 46. Similar to the
guide groove 51, the guide groove 52 is formed on the inner peripheral surface of
the cylindrical body 46, and extends along the direction of the axis O of the cylindrical
body 46. Then, the guide groove 52 is also configured so that the axis O side of the
cylindrical body 46 is open, and has a bottom surface on an inner peripheral surface
side of the cylindrical body 46.
[0062] In addition, as is understood from Fig. 6, at least a portion of the bottom surfaces
of the guide grooves 51 and 52 have curved surfaces 51a and 52a which are curved with
respect to a direction along the axis O of the cylindrical body 46. It is preferable
that the curved surfaces 51a and 52a be configured as follows in a cross section illustrated
in Fig. 6.
[0063] The curved surfaces 51a and 52a are disposed to oppose each other so as to be line-symmetrical
across the axis O of the cylindrical body 46, and a gap between the curved surfaces
51a and 52a is narrowed as the curved surfaces 51a and 52a are away from the bottom
portion 49 side (side inserted into the photosensitive drum 35). In this manner, it
is preferable to form the curved surfaces to be close to each other. As will be described
later, this can hold the intermediate member 60 so as not to be detached from the
body 45.
[0064] It is preferable that the curved surfaces 51a and 52a have an arc shape and belong
to the same circle, and that the center of the circle be located on the axis O. This
can hold the intermediate member 60 in the body 45 in the direction along the axis
O without looseness. Accordingly, it is possible to swing (tilt) the shaft member
70 by smoothly guiding the rotation of the intermediate member 60.
[0065] In addition, when the bottom portion 49 is provided, the bottom portion 49 may be
arranged on the circumference of the circle to which the curved surfaces 51a and 52a
belong so that an intersection point (point illustrated by B in Fig. 6) with a surface
on the curved surfaces 51a and 52a side is present between the axis O and the bottom
portion 49 of the cylindrical body 46.
[0066] A material configuring the body 45 is not particularly limited, but it is possible
to use a resin such as polyacetal, polycarbonate, or PPS. Here, in order to improve
rigidity of the member, glass fibers or carbon fibers may be mixed with the resin,
depending on load torques. In addition, in order to obtain a smooth swing operation
when the intermediate member 60 is attached to the body 45, sliding performance may
be improved by causing the resin to contain at least one type among fluorine, polyethylene,
and silicone rubber. In addition, the resin may be coated with fluorine, or lubricant
may be applied to the resin.
[0067] Referring back to Fig. 4, the intermediate member 60 will be described. As is understood
from Fig. 4, the intermediate member 60 is an annular member which is partially cut
out. Fig. 7 illustrates the intermediate member 60. Fig. 7(a) is a perspective view,
Fig. 7(b) is a front view, and Fig. 7(c) is a cross-sectional view taken along a line
illustrated by VIIc-VIIc in Fig. 7(b).
[0068] The intermediate member 60 has an annular shape in which a cutout portion 60a is
partially disposed.
[0069] In the intermediate member 60, a portion on an outer periphery thereof functions
as a guided portion by being inserted into the inner side of a pair of grooves among
the guide grooves 51, 52, 53, and 54 which are included in the holding portion 50
of the above-described body 45. Therefore, the outer diameter of the intermediate
member 60 has a size which enables the intermediate member 60 to slide therein by
being accommodated inside the pair of guide grooves in which the outer peripheral
portion of the intermediate member 60 is arranged. When at least a portion of the
bottom surface of the guide grooves 51, 52, 53, and 54 has an arc shape as described
above, and when the arc belongs to the same circle in the pair of opposing guide grooves,
it is preferable that the diameter of the circle be the same as the outer diameter
of the intermediate member 60. This enables the intermediate member 60 to be smoothly
and rotated between the guide grooves, and can suppress the looseness.
[0070] In contrast, the proximal end portion of the shaft member 70 (to be described later)
is arranged on an annular inner side of the intermediate member 60. Accordingly, the
annular inner side may have a size and a form which can accommodate at least a portion
of the proximal end portion inside the intermediate member 60. In the present embodiment,
the proximal end portion of the shaft member 70 is a spherical body 90 (refer to Figs.
8(a) and 8(b)). Accordingly, the inner diameter of the intermediate member 60 can
be configured to be the same as the diameter of the spherical body 90. In addition,
as is understood from Fig. 7(c), the inner peripheral surface of the intermediate
member 60 is also curved in an arc shape in a direction along the axis of the ring
(vertical direction on a paper surface in Fig. 7(c)). The curve can match the curve
on the outer periphery of the spherical body 90. This enables the intermediate member
60 and the spherical body 90 to be more suitably combined with each other.
[0071] Then, the size (that is, thickness) in the direction along the axis of the ring of
the intermediate member 60 is substantially the same as the width of the guide grooves
51 and 52 which are formed in the holding portion 50 of the above-described body 45.
[0072] The cutout portion 60a of the intermediate member 60 has a size and a shape in which
at least a portion of a rotary shaft 85 (refer to Figs. 8(a) and 8(b)) of at least
the shaft member 70 (to be described later) can be arranged thereinside. Therefore,
an end surface 60b of the intermediate member 60 in which the cutout portion 60a is
formed can also match the shape of the rotary shaft 85. In the present embodiment,
an enlarged diameter portion 85a is disposed in the rotary shaft 85, and a tapered
portion is disposed herein (refer to Figs. 8(a) and 8(b)). Accordingly, the end surface
60b of the intermediate member 60 is formed so as to have a valley in a V-shape which
can receive the tapered portion.
[0073] Two grooves 61 and 62 extending outward from an inner peripheral surface of the ring
are disposed in the intermediate member 60. The two grooves 61 and 62 are disposed
at positions opposing each other along a diameter of the intermediate member 60. Both
ends of a rotation force transmission pin 95 (refer to Fig. 8) of the shaft member
70 (to be described later) are respectively inserted into the grooves 61 and 62. Therefore,
a shape and arrangement of the grooves 61 and 62 are configured so that the end portions
of the rotation force transmission pin 95 can be respectively inserted into the grooves
61 and 62.
[0074] In addition, it is preferable that pieces 61a and 62a remain in one of the grooves
61 and 62 in the axis direction of the ring of the intermediate member 60, and that
the grooves 61 and 62 do not penetrate in the direction along the axis. In this manner,
when the shaft member 70 is assembled to the intermediate member 60 and the rotation
force is applied to the shaft member 70 from the apparatus body 10, the rotation force
transmission pin 95 is caught on by the pieces 61a and 62a so that the rotation fore
can be properly transmitted to the intermediate member 60. Therefore, in view of the
rotation of the rotation force transmission pin 95, as is well understood from Figs.
7(a) to 7(c), the piece 61a of the groove 61 and the piece 62a of the groove 62 are
disposed on different sides in the axial direction of the intermediate member 60.
[0075] If a distal end of the rotation force transmission pin 95 extends to reach the inside
of the guide grooves 51 and 52 of the holding portion 50 of the body 45, the distal
end of the rotation force transmission pin 95 is caught on by a lateral wall of the
guide grooves 51 and 52 when rotated. Accordingly, since the rotation force can be
transmitted, the pieces 61a and 62a may not be necessarily disposed.
[0076] In addition, an opening portion opposing the pieces 61a and 62a within the grooves
61 and 62 may be slightly narrowed as compared to the inside of the groove. Specifically,
the opening portion can be configured to have an opening which is slightly smaller
than a diameter of the rotation force transmission pin 95. In this manner, the rotation
force transmission pin 95 which has entered the inside of the grooves 61 and 62 once
is less likely to slip out from the grooves 61 and 62 by the narrowed opening portion.
[0077] A material configuring the intermediate member 60 is not particularly limited, but
it is possible to use a resin such as polyacetal, polycarbonate, and PPS. Here, in
order to improve rigidity of the member, glass fibers or carbon fibers may be mixed
with the resin, depending on load torques. In addition, in order to obtain a smooth
swing operation when the intermediate member 60 is attached to the body 45, sliding
performance may be improved by causing the resin to contain at least one type among
fluorine, polyethylene, and silicone rubber. In addition, the resin may be coated
with fluorine, or lubricant may be applied to the resin.
[0078] Referring back to Fig. 3, the shaft member 70 within the end member 40 will be described.
Fig. 8(a) illustrates a cross-sectional view taken along VIIIa-VIIIa of the shaft
member 70 illustrated in Fig. 3(b), and Fig. 8(b) illustrates a cross-sectional view
taken along VIIIb-VIIIb of the shaft member 70 illustrated in Fig. 3(b), respectively.
Two cross sections are shifted by 90° around the axis. As is understood from Figs.
3(b), 8(a), and 8(b), the shaft member 70 includes a coupling member 71, the rotary
shaft 85, the spherical body 90, and the rotation force transmission pin 95.
[0079] The coupling member 71 is a portion which functions as a rotation force receiving
portion for receiving the rotation driving force from the apparatus body 10 (refer
to Fig. 1). Fig. 9 illustrates an enlarged view of the coupling member 71. As is understood
from Figs. 3(b), 8(a), 8(b), and 9, the coupling member 71 is a circular dish-shaped
member, and an inside thereof has a bottom portion 73 in which a conical concave portion
73a is disposed so that a portion through which the axis passes is the deepest.
[0080] In addition, a cylindrical engagement wall 74 is erected along an edge of a surface
on one surface side (opposite side to the side having the rotary shaft 85) within
surfaces of the bottom portion 73. Two pairs of grooves 74a and 74b which oppose each
other across the axis of the shaft member 70 are disposed on the engagement wall 74.
One pair of the grooves 74a and the other pair of the grooves 74b are shifted by 90°
around the axis.
[0081] As clearly illustrated in Fig. 9, a convex portion 75 is disposed on one lateral
wall of the groove in the respective grooves 74a and 74b, and the bottom portion 73
side thereof is provided with a recess 75a in the circumferential direction. In this
manner, as will be described later, a pin 11b of the drive shaft 11 of the apparatus
body 10 engages with the recess 75a. Accordingly, the pin 11b is prevented from slipping
out, and the rotation force is properly transmitted (refer to Fig. 12(b)).
[0082] In addition, a tilted surface 74c is formed on the other side lateral wall of the
respective grooves 74a and 74b, thereby facilitating introduction of the above-described
pin 11b into the groove.
[0083] Therefore, a width of the groove 74a illustrated by C in Fig. 9 is slightly larger
than a diameter of the pin 11b (refer to Fig. 12(b)), and is narrower than a diameter
of a shaft portion 11a so that the shaft portion 11a of the drive shaft 11 cannot
pass therethrough. An inner side diameter of the engagement wall 74 which is illustrated
by D in Fig. 9 is formed to be slightly larger than the diameter of the shaft portion
11a of the drive shaft 11, but is approximately the same. How the rotation force can
be received from the drive shaft 11 will be described later.
[0084] The present embodiment employs four (two pairs) grooves on the engagement wall, but
the number is not particularly limited thereto. Two (one pair), six (three pairs)
or more grooves may be employed. In addition, a form of the coupling member 71 has
been specifically described as an example, but the present embodiment is not necessarily
limited to the form. Any shape may be employed as long as the drive shaft 11 of the
apparatus body 10 can engage with and disengage from the coupling member 71.
[0085] The rotary shaft 85 is a columnar shaft-shaped member which functions as a rotation
force transmission portion for transmitting the rotation force received by the coupling
member 71. Therefore, the above-described coupling member 71 is disposed in one end
of the rotary shaft 85. In addition, in the present embodiment, the rotary shaft 85
is configured to have the enlarged diameter portion 85a in which the diameter of the
rotary shaft is partially enlarged. The enlarged diameter portion 85a and the other
portion are continuous with each other on a surface tilted in a tapered shape.
[0086] The spherical body 90 functions as a proximal end portion, and is a spherical member
in the present embodiment, as is understood from Figs. 8(a) and 8(b). The spherical
body 90 is included in an end portion opposite to the side having the coupling member
71 within end portions of the rotary shaft 85. In this case, it is preferable to cause
the axis of the rotary shaft 85 and the center of the spherical body 90 to coincide
with each other as much as possible. This enables the photosensitive drum 35 to be
more stably rotated. In addition, the diameter of the spherical body 90 is configured
to have a size to be accommodated inside the ring of the intermediate member 60 of
the above-described bearing member 41. It is preferable to configure the diameter
so as to be approximately the same as the inner diameter of the ring.
[0087] In the present embodiment, a case has been described in which the proximal end portion
has a spherical shape, but the present embodiment is not limited thereto. For example,
the present embodiment is not particularly limited as long as the proximal end portion
has a form which does not interfere with the swing of the shaft member, such as a
partially spherical shape and an oval shape in which curved surfaces are combinedly
formed.
[0088] The rotation force transmission pin 95 is a columnar shaft-shaped member which forms
a rotation force transmission projection which projects from the proximal end portion
by passing through the center of the spherical body 90, and by both ends protruding
from the spherical body 90 after penetrating the spherical body 90. The axis of the
rotation force transmission pin 95 is disposed so as to be orthogonal to the axis
of the above-described rotary shaft 85.
[0089] A material configuring the shaft member 70 is not particularly limited, but it is
possible to use a resin such as polyacetal, polycarbonate, and PPS. However, in order
to improve rigidity of the member, glass fibers or carbon fibers may be mixed with
the resin, depending on load torques. In addition, the rigidity may be further strengthened
by inserting metal into the resin, or the shaft member 70 may be entirely or partially
manufactured by using the metal.
[0090] The bearing member 41 and the shaft member 70 are combined as follows so as to configure
the end member 40. Description of this combination will further facilitate understanding
of a shape, a size, and a positional relationship which are provided for the bearing
member 41 and the shaft member 70. Fig. 10(a) illustrates a cross-sectional view of
the end member 40 taken along line VIIIa-VIIIa illustrated in Fig. 3(b), and Fig.
10(b) illustrates a cross-sectional view taken along line VIIIb-VIIIb illustrated
in Fig. 3(b), respectively. In addition, Fig. 11(a) illustrates an example of a tilting
posture of the shaft member 70 in a viewpoint illustrated in Fig. 10(a), and Fig.
11(b) illustrates an example of a tilting posture of the shaft member 70 in a viewpoint
illustrated in Fig. 10(b), respectively.
[0091] As is particularly well understood from Fig. 10(b), the spherical body 90 is arranged
inside the ring of the intermediate member 60, and the rotation force transmission
pin 95 is inserted into the grooves 61 and 62 of the intermediate member 60. This
causes the intermediate member 60 and the shaft member 70 to be combined with each
other. Therefore, as illustrated by arrow XIa in Fig. 11(a), the shaft member 70 can
swing around the axis of the rotation force transmission pin 95 with respect to the
intermediate member 60.
[0092] In contrast, as is well understood from Figs. 10(a) and 10(b), in the intermediate
member 60 in which the shaft member 70 is arranged, the outer peripheral portion of
the intermediate member 60 is fitted into the guide grooves 51 and 52 so that the
thickness direction of the intermediate member 60 is the width direction of the guide
grooves 51 and 52 formed in the holding portion 50 of the body 45. Therefore, the
outer peripheral portion of the intermediate member 60 is arranged inside the guide
grooves 51 and 52, and the intermediate member 60 can slidably move inside the guide
grooves 51 and 52. As a result, the intermediate member 60 can be rotated inside the
body 45 as illustrated by arrow XIb in Fig. 11(b).
[0093] As in the present embodiment, if the curved surfaces 51a and 52a formed on the bottom
surface of the guide grooves 51 and 52 are located on a circle and the outer periphery
of the intermediate member 60 is formed to have substantially the same diameter as
that of the circle, the intermediate member 60 is accommodated in the body without
looseness as illustrated in Fig. 10(b). Accordingly, the end member 40 is allowed
to more excellently and accurately transmit the rotation.
[0094] As described above, in the end member 40 of the present embodiment, the intermediate
member 60 is held by the guide grooves 51 and 52 formed in the body 45 so as not to
slip out, and the shaft member 70 is held by the intermediate member 60 so as not
to slip out. Therefore, the shaft member 70 is not directly held by the body 45.
[0095] In addition, this assembly work of the end member 40 can be carried out by first
arranging the shaft member 70 in the intermediate member 60 and attaching the intermediate
member 60 to the body 45. In this case, when the intermediate member 60 is arranged
inside the guide grooves 51 and 52 of the holding portion 50, the assembly work can
be carried out through elastic deformation using a weak force. Therefore, it is possible
to assemble the shaft member 70 to the bearing member 41 easily and with increased
productivity. In addition, not only the assembly work is facilitated, but also the
detachment work is similarly facilitated. Accordingly, the reuse is also facilitated.
Particularly, in this case, it is not necessary to deform the shaft member 70 during
the insertion and the detachment. Accordingly, there is no more possibility of damage.
In addition, since the detachment is facilitated, workability can also be improved.
[0096] As described above, the shaft member 70 is arranged inside the bearing member 41,
thereby enabling the shaft member 70 to swing as illustrated in Figs. 11(a) and 11(b).
That is, in a viewpoint illustrated in Fig. 11(a), the shaft member 70 can swing around
the axis of the rotation force transmission pin 95 as illustrated by arrow XIa. In
contrast, in a viewpoint illustrated in Fig. 11(b), the shaft member 70 can swing
to follow the rotation of the intermediate member 60 as illustrated by arrow XIb.
The swing illustrated in Fig. 10(a) and the swing illustrated in Fig. 11(b) are swings
in a direction in which the swings are orthogonal to each other.
[0097] In addition, when the driving force is received from the apparatus body 10, the shaft
member 70 receives the rotation force acting around the axis as illustrated by arrow
X in Figs. 10(a) and 10(b). In this case, both end portions of the rotation force
transmission pin 95 of the shaft member 70 press the intermediate member 60, and the
intermediate member 60 is caught on by the lateral wall of the guide grooves 51 and
52 of the body 45. In this manner, the rotation force can be transmitted to the photosensitive
drum 35. When the distal end of the rotation force transmission pin 95 is configured
to reach the inside of the guide grooves 51 and 52, even if the pieces 61a and 62a
(refer to Fig. 7(c)) are not provided, the distal end of the rotation force transmission
pin 95 is caught on by the lateral wall of the guide grooves 51 and 52 of the body
45. In this manner, the rotation force can be transmitted to the photosensitive drum
35.
[0098] As described above, according to the end member 40, the swing of the shaft member
70 in at least one direction enables the intermediate member 60 and the body 45 to
slide and swing, thereby allowing a smooth operation. In this case, the swing has
no relationship with a form of the shaft member. Accordingly, even if the shaft member
side has slightly uneven dimensions, it is possible to ensure sufficiently smooth
swing. In addition, even if an angle of the swing increases, there is no possibility
that the shaft member 70 slips out therefrom. Therefore, it is possible to increase
the angle of the swing. This can minimize a gap between the photosensitive drum (process
cartridge) and the drive shaft on the apparatus body side. Accordingly, it is possible
to miniaturize the apparatus body.
[0099] In addition, according to the end member 40, it is not necessary to dispose the groove
(introduction groove) for introducing the rotation force transmission pin into the
swing groove as disclosed in Non Patent Literature 1. It is possible to solve the
problem that the shaft member accidentally slips out during the operation.
[0100] The above-described configuration enables the shaft member 70 to be pivotally moved
(swing), to transmit the rotation force, and to be held by the bearing member 41.
[0101] The end member 40 is attached to the photosensitive drum 35 by inserting the end
portion on a side where the shaft member 70 does not protrude within the end member
40 into the photosensitive drum 35 after the end member 40 is assembled as illustrated
in Figs. 10(a) and 10(b). This end member 40 properly applies the rotation force to
the photosensitive drum 35 when the process cartridge 20 is mounted on the apparatus
body 10, and enables the process cartridge 20 to be easily attached and detached.
[0102] As described above, the photosensitive drum unit 30, the charging roller unit 22,
the developing roller unit 23, the regulating member 24, and the cleaning blade 25
are rotatably accommodated inside the housing 21 of the process cartridge 20 (refer
to Fig. 2). That is, each member fulfills its function by being rotated inside the
housing when necessary.
[0103] Then, in the present embodiment, at least the coupling member 71 within the shaft
member 70 of the photosensitive drum unit 30 is arranged to be exposed from the housing
21. As will be described later, this enables the rotation driving force to be obtained
from the apparatus body 10, and facilitates the attachment and detachment between
the apparatus body 10 and the process cartridge 20.
[0104] Here, each member included in the process cartridge 20 has been described as an example,
but a member included herein is not limited thereto. It is preferable to provide a
member, a portion, and a developer which are normally included in other process cartridges.
[0105] Next, the apparatus body 10 will be described. The apparatus body 10 according to
the present embodiment is a laser printer. The laser printer is operated in a posture
where the above-described process cartridge 20 is mounted thereon. When forming an
image, the photosensitive drum 35 is rotated, and the charging roller unit is used
in charging. In this state, the laser printer uses various optical members included
herein, emits laser beams corresponding to image information to the photosensitive
drum 35, and can obtain an electrostatic latent image based on the image information.
The latent image is developed by the developing roller unit 23.
[0106] In contrast, a recording medium such as a paper sheet is set on the apparatus body
10, and is transported to a transfer position by a feeding roller and a transport
roller which are disposed in the apparatus body 10. A transfer roller 10a (refer to
Fig. 2) is arranged at the transfer position, and a voltage is applied to the transfer
roller 10a whenever the recording medium passes therethrough. In this manner, the
image is transferred to the recording medium from the photosensitive drum 35. Thereafter,
heat and pressure are applied to the recording medium, thereby fixing the image onto
the recording medium. Then, the recording medium on which the image is formed is discharged
from the apparatus body 10 by a discharge roller.
[0107] As described above, in a posture where the process cartridge 20 is mounted thereon,
the apparatus body 10 applies the rotation driving force to the photosensitive drum
unit 30. Therefore, how the rotation driving force is applied from the apparatus body
10 to the photosensitive drum unit 30 in the posture where the process cartridge 20
is mounted thereon will be described.
[0108] The rotation driving force is applied to the process cartridge 20 by the drive shaft
11 serving as a rotation force applying portion of the apparatus body 10. Fig. 12(a)
illustrates a shape of a distal end portion of the drive shaft 11. As is understood
from Fig. 12(a), the drive shaft 11 has a shaft portion 11a which is a columnar shaft
member whose distal end has a spherical surface, and a columnar pin 11b serving as
a rotation force applying portion which protrudes in a direction orthogonal to the
rotation axis illustrated by a dashed line of the shaft portion 11a. A gear train
is formed on a side opposite to the distal end side illustrated in Fig. 12(a) within
the drive shaft 11 so that the drive shaft 11 can be rotated around the axis of the
shaft portion 11a of the drive shaft 11. The drive shaft 11 is connected to a motor
serving as a drive source via the gear train.
[0109] In addition, the drive shaft 11 is arranged to protrude on a trajectory of a movement
for attachment and detachment at a substantially right angle, with respect to a movement
direction for attaching and detaching the process cartridge 20 illustrated in Fig.
1 to and from the apparatus body 10. Therefore, for the attachment and detachment
of the process cartridge 20, it is necessary to attach and detach the shaft member
70 to and from this drive shaft 11. Then, according to the above-described end member
40, the attachment and detachment between the shaft member 70 and the drive shaft
11 are facilitated. A specific aspect of the attachment and detachment will be described
in detail later.
[0110] In a posture where the process cartridge 20 is mounted on the apparatus body 10,
the drive shaft 11 engages with the coupling member 71 of the shaft member 70 of the
end member 40, thereby transmitting the rotation force. Fig. 12(b) illustrates a scene
where the coupling member 71 of the end member 40 engages with the drive shaft 11.
As is understood from Fig. 12(b), in a posture where the drive shaft 11 and the coupling
member 71 engage with each other, the drive shaft 11 and the coupling member 71 are
arranged to abut onto each other so that the axis of the shaft portion 11a of the
drive shaft 11 coincides with the axis of the coupling member 71. In this case, the
pin 11b of the drive shaft 11 is arranged inside the groove 74a or the groove 74b
which the coupling member 71 opposes (in Fig. 12(b), arranged inside the groove 74a).
This causes the coupling member 71 to be rotated to follow the rotation of the drive
shaft 11, and causes the photosensitive drum unit 30 to be rotated.
[0111] As described above, a posture where the rotation force is transmitted is a posture
where the axis of the shaft portion 11a and the axis of the coupling member 71 are
arranged coaxially and the pin 11b is located inside the groove 74a or the groove
74b of the coupling member 71.
[0112] Next, an example of an operation of the drive shaft 11 and the photosensitive drum
unit 30 when the process cartridge 20 is mounted on the apparatus body 10 will be
described. Fig. 13 illustrates a view for describing the example. Fig. 13(a) is a
view illustrating one scene where the end member 40 engages with the drive shaft 11,
and Fig. 13(b) is a view illustrating another scene where the end member 40 engages
with the drive shaft 11. In Fig. 13, the operations are sequentially illustrated by
using Figs. 13(a) and 13(b), and rightward-leftward direction in the drawing paper
represents an extending direction of the axis. In addition, these are the scenes where
the process cartridge 20 is moved to the lower side in the drawing paper and is mounted
on the apparatus body 10.
[0113] As illustrated in Fig. 13(a), the coupling member 71 of the shaft member 70 is first
arranged in a posture of being tilted to the drive shaft 11 side. It is preferable
that this posture be a posture where the shaft member 70 is most tilted. If the process
cartridge 20 is moved to the lower side in the drawing paper from this posture, the
distal end of the drive shaft 11 comes into contact with the inner side of the bottom
portion 73 or the engagement wall 74 of the coupling member 71 so as to be caught
thereon. If the process cartridge 20 is further pressed into the apparatus body 10,
the drive shaft 11 which comes into contact with the coupling member 71 so as to be
caught thereon causes the shaft member 70 tilted with respect to the axial direction
to be pivotally moved (swing) so that the shaft member 70 moves close to the axial
direction. Then, the pin 11b is inserted into the groove 74a.
[0114] Then, if the process cartridge 20 is further pressed into the apparatus body 10 in
the mounting direction, as illustrated in Fig. 13(b), the axis of the tilted shaft
member 70 coincides with the axis of the drive shaft 11, and the axes of the drive
shaft 11, the shaft member 70, the bearing member 41, and the photosensitive drum
35 coincide with one another, thereby adopting the posture illustrated in Fig. 12(b).
This causes the rotation force to be properly applied from the drive shaft 11 to the
shaft member 70, the bearing member 41, and the photosensitive drum 35. The rotation
force is finally applied to the process cartridge 20.
[0115] In contrast, an operation of the drive shaft 11 and the photosensitive drum unit
30 when the process cartridge 20 is detached from the apparatus body 10 may be performed
by reversing the above-described order.
[0116] As described above, the process cartridge 20 can be detached from the apparatus body
10 so as to be pulled out in a direction different from the axial direction of the
drive shaft 11 of the apparatus body 10. In addition, the process cartridge 20 can
be mounted on the apparatus body 10 so as to be pressed into the apparatus body 10.
[0117] Next, a second embodiment will be described. Herein, description will be made by
focusing on portions different from those of the process cartridge 20 according to
the first embodiment. The same reference numerals are given to elements common to
those of the process cartridge 20, and description thereof will be omitted.
[0118] Fig. 14 is a view for describing the second embodiment, and is a perspective view
of an end member 140. Fig. 14 is a view illustrated in the same viewpoint in Fig.
2(b). The end member 140 is a member attached to an end portion opposite to the lid
member 36 within the end portion of the photosensitive drum 35, and includes a bearing
member 141 and the shaft member 70. The shaft member 70 is the same as the above-described
one.
[0119] The bearing member 141 is a member fixed to the end portion of the photosensitive
drum 35. Fig. 15 illustrates an exploded perspective view of the bearing member 141.
As is understood from Fig. 15, the bearing member 141 includes a body 145 and an intermediate
member 160. Hereinafter, the body 145 and the intermediate member 160 will be respectively
described.
[0120] Fig. 16(a) illustrates a view when the body 145 is viewed from a side into which
the intermediate member 160 is inserted, and Fig. 16(b) illustrates a perspective
view when the body 145 is viewed from an angle different from that in Fig. 15, respectively.
In addition, Fig. 17 illustrates a cross-sectional view taken along the axis including
a line illustrated by XVII-XVII in Figs. 15, 16(a), and 16(b). Furthermore, Fig. 18(a)
illustrates a cross-sectional view taken along the axis including a line illustrated
by XVIIIa-XVIIIa in Figs. 15, 16(a), 16(b), and 17. Then, Fig. 18(b) illustrates a
cross-sectional view taken along the axis including a line illustrated by XVIIIb-XVIIIb
in Figs. 16(a) and 17.
[0121] In the present embodiment, as is understood from Figs. 14 to 18, the body 145 is
different from the body 45 in a form of a bottom portion 149 and a holding portion.
Other elements such as the cylindrical body 46, the contact wall 47, and the gear
48 become the same as those of the body 45 in the description, and thus, description
thereof will be omitted here.
[0122] The bottom portion 149 extending in a rod shape in a radial direction of the cylindrical
body 46 is disposed in a cylindrical inner side of the cylindrical body 46 so as to
close at least a portion of the inner side of the cylindrical body 46. Furthermore,
a holding portion 150 is disposed on an inner side opposite to a side fixed to the
photosensitive drum 35 across the bottom portion 149 within the inner side of the
cylindrical body 46.
[0123] The holding portion 150 forms guide surfaces 151 and 152 serving as an intermediate
member guide on the inner side of the cylindrical body 46. Therefore, the holding
portion 150 is arranged so that two projections 150a protrude from the inner surface
of the cylindrical body 46 toward the axis of the cylindrical body 46 and face each
other. A groove 150b is formed between the two projections 150a.
[0124] A form of the holding portion 150 will be further described in detail.
[0125] As is well understood from Figs. 16(a) and 16(b), the two projections 150a are arranged
to face each other, and a gap is formed therebetween, thereby configuring the groove
150b. In addition, the projection 150a has a concave portion 150c so that a sphere
having the center on the axis of the cylindrical body 46 within the projection 150a
is partially hollowed. A spherical surface of the concave portion 150c has a shape
which enables the spherical body 90 of the shaft member 70 to be accommodated therein.
However, the concave portion 150c may not necessarily have the spherical surface.
[0126] Furthermore, a guide member insertion groove 150d which extends in the radial direction
orthogonal to the radial direction of the cylindrical body 46 in which the groove
150b extends is formed on the bottom of the concave portion 150c. The guide member
insertion groove 150d has a form which enables a guide member 165 of the intermediate
member 160 (to be described later) to be inserted.
[0127] In addition, as is well understood from Figs. 17 and 18(b), a surface is also formed
on a side opposite to the concave portion 150c within the projection 150a (that is,
a side opposing the bottom portion 149 within the holding portion 150). As is understood
from Fig. 18(b), the surface has an arc shape. These serve as guide surfaces 151 and
152. The guide surfaces 151 and 152 have a curved surface formed so as to be curved
along the extending direction of the groove 150b. The guide member 165 of the intermediate
member 160 slides on the guide surfaces 151 and 152, thereby causing the shaft member
70 to swing. The swing will be described later.
[0128] Therefore, the guide member insertion groove 150d formed on the bottom portion of
the concave portion 150c is a groove which causes the concave portion 150c and a rear
surface (surface on which the guide surfaces 151 and 152 are present) of the holding
portion 150 to communicate with each other, and which causes the guide member 165
to reach the guide surfaces 151 and 152.
[0129] It is preferable that the holding portion 150 having this form be further formed
as follows.
[0130] The groove width of the groove 150b is not particularly limited, but it is preferable
that the width be arranged to be approximately the same as the thickness of the intermediate
member 160. This can suppress the looseness of the shaft member 70.
[0131] A shape of the inner surface of the concave portion 150c is not particularly limited
as long as the shape enables the proximal end portion of the shaft member 70 to be
accommodated therein. However, when the proximal end portion of the shaft member 70
is the spherical body 90, it is preferable to provide a curved surface having the
same radius as that of the spherical body 90. This also prevents the looseness of
the shaft member 70.
[0132] It is preferable that the guide member 165 of the intermediate member 160 can be
inserted into the guide member insertion groove 150d, and that the guide member insertion
groove 150d adopt a snap-fit (interference-fit in the entrance portion) structure
with respect to the guide member 165. This can prevent the intermediate member 160
from slipping out from the body 145. For example, the snap-fit structure includes
snap-fit structures 150e and 150f which are pieces protruding from a wall surface
of the guide member insertion groove 150d.
[0133] The guide surfaces 151 and 152 are surfaces for guiding the intermediate member 160
so that the shaft member 70 properly swings, and surfaces for determining the swing
of the shaft member 70. Therefore, it is preferable that the guide surfaces 151 and
152 have an arc shape in a cross section illustrated in Fig. 18(b) from a viewpoint
that stable swing can be obtained. That is, it is preferable that the guide surfaces
151 and 152 have an arc shape around the center of the swing of the shaft member.
This enables a smooth swing. In addition, in the present embodiment, an arc of the
concave portion 150c is also configured to be an arc which is concentric with the
guide surfaces 151 and 152.
[0134] A material configuring the body 145 is the same as that of the above-described body
45.
[0135] Referring back to Fig. 15, the intermediate member 160 will be described. As is understood
from Fig. 15, the intermediate member 160 is an annular member which is partially
cut out. Fig. 19 illustrates the intermediate member 160. Fig. 19(a) is a perspective
view, Fig. 19(b) is a front view, and Fig. 19(c) is a cross-sectional view taken along
a line illustrated by XIXc-XIXc in Fig. 19(b).
[0136] The intermediate member 160 has an annular shape in which a cutout portion 160a is
partially disposed.
[0137] In the intermediate member 160, an outer peripheral portion thereof is arranged in
the groove 150b included in the holding portion 150 of the body 145. Therefore, the
outer diameter of the intermediate member 160 has a size which enables the intermediate
member 160 to be inserted into the groove 150b.
[0138] In contrast, the proximal end portion of the shaft member 70 is arranged on an annular
inner side of the intermediate member 160. Accordingly, the annular inner side may
have a size and a form which can accommodate the proximal end portion inside the intermediate
member 160. In the present embodiment, the proximal end portion of the shaft member
70 is the spherical body 90. Accordingly, the inner diameter of the intermediate member
160 can be configured to be the same as the diameter of the spherical body 90. In
addition, as is understood from Fig. 19(c), the inner peripheral surface of the intermediate
member 160 is also curved in an arc shape in a direction along the axis of the ring
(vertical direction on the drawing paper in Fig. 19(c)). The curve can match the curve
formed by the diameter of the spherical body 90. This enables the intermediate member
160 and the spherical body 90 to be more suitably combined with each other.
[0139] Then, the size (that is, thickness) in the direction along the axis of the ring of
the intermediate member 160 is substantially the same as the width of the guide groove
150b formed in the holding portion 150 of the above-described body 145. This can prevent
the looseness.
[0140] The cutout portion 160a of the intermediate member 160 has a size and a shape which
enable at least the rotary shaft 85 (refer to Fig. 8) of the shaft member 70 to be
arranged thereinside.
[0141] Two grooves 161 and 162 extending outward from the inner peripheral surface of the
ring are disposed in the intermediate member 160. The two grooves 161 and 162 are
disposed to oppose each other along the diameter of the intermediate member 160. Both
ends of the rotation force transmission pin 95 (refer to Fig. 8) of the shaft member
70 are respectively inserted into the grooves 161 and 162. Therefore, a shape and
arrangement of the grooves 161 and 162 are configured so that the end portions of
the rotation force transmission pin 95 can be respectively inserted into the grooves
161 and 162.
[0142] In addition, it is preferable that pieces 161a and 162a remain in one of the grooves
161 and 162 in the direction along the axis of the ring of the intermediate member
160, and that the grooves 161 and 162 do not penetrate in the direction along the
axis. In this manner, when the shaft member 70 is assembled to the intermediate member
160 and the rotation force is applied to the shaft member 70 from the apparatus body
10, the rotation force transmission pin 95 is caught on by the pieces 161a and 162a
so that the rotation fore can be properly transmitted to the intermediate member 160.
Therefore, in view of the rotation of the rotation force transmission pin 95, as is
well understood from Figs. 19(a) to 19(c), the piece 161a of the groove 161 and the
piece 162a of the groove 162 are disposed on different sides in the axial direction
of the intermediate member 160.
[0143] If a distal end of the rotation force transmission pin 95 extends to reach the inside
of the guide groove 150b of the holding portion 150 of the body 145, the distal end
of the rotation force transmission pin 95 is caught on by a lateral wall of the guide
groove 150b when rotated. Accordingly, since the rotation force can be transmitted,
the pieces 161a and 162a may not be necessarily disposed.
[0144] In addition, an opening portion opposing the pieces 161a and 162a within the grooves
161 and 162 may be slightly narrowed as compared to the inside of the groove. Specifically,
the opening portion can be configured to have an opening which is slightly smaller
than the diameter of the rotation force transmission pin 95. In this manner, the rotation
force transmission pin 95 which has entered the inside of the grooves 161 and 162
once is less likely to slip out from the grooves 161 and 162 by the narrowed opening
portion.
[0145] Furthermore, the guide member 165 which functions as a guided portion respectively
from annular-shaped front and rear surfaces and extends along the axial direction
of the ring is arranged so as to protrude in the intermediate member 160. In the present
embodiment, the guide member 165 is a columnar pin. A position where the guide member
165 is arranged is not particularly limited. As will be described later, the guide
member 165 may be arranged at a position where the guide member 165 can slide on the
guide surfaces 151 and 152 when the intermediate member 160 is arranged in the body
145. In addition, a shape of the guide member 165 is not limited to the column. The
guide member 165 may have a cross-sectional shape of a quadrangular column, a triangular
column, or others.
[0146] A material configuring the intermediate member 160 is not particularly limited, but
it is possible to use a resin such as polyacetal, polycarbonate, and PPS. Here, in
order to improve rigidity of the member, glass fibers or carbon fibers may be mixed
with the resin, depending on load torques. In addition, in order to obtain a smooth
swing operation when the intermediate member 160 is attached to the body 145, sliding
performance may be improved by causing the resin to contain at least one type among
fluorine, polyethylene, and silicone rubber. In addition, the resin may be coated
with fluorine, or lubricant may be applied to the resin.
[0147] The bearing member 141 and the shaft member 70 are combined with each other as follows
so as to configure the end member 140. Description of this combination will further
facilitate understanding of a form included in the bearing member 141 and the shaft
member 70, or a form and a size of the members.
[0148] Fig. 20 illustrates a cross-sectional view of the end member 140 which is taken along
line XX-XX illustrated in Fig. 14, and Fig. 21(a) illustrates a cross-sectional view
of the end member 140 which is taken along line XXIa-XXIa illustrated in Fig. 14,
respectively. Fig. 21(b) illustrates a view focusing on a positional relationship
between the body 145 and the guide member 165 included in the intermediate member
160, within a cross section of the end member 140 which is taken along line XXIb-XXIb
illustrated in Fig. 20. Therefore, the shaft member 70 is omitted in Fig. 21(b).
[0149] In addition, Fig. 22 illustrates an example of a posture where the shaft member 70
is tilted in a viewpoint illustrated in Fig. 20, Fig. 23(a) illustrates an example
of a posture where the shaft member 70 is tilted in a viewpoint illustrated in Fig.
21(a), and Fig. 23(b) illustrates an example of a posture where the shaft member 70
is tilted in the posture illustrated in Fig. 21(b), respectively.
[0150] As is understood particularly well from Fig. 21(a), the spherical body 90 is arranged
inside the ring of the intermediate member 160, and the rotation force transmission
pin 95 is inserted into the grooves 161 and 162 of the intermediate member 160. In
this manner, the intermediate member 160 and the shaft member 70 are combined with
each other. Therefore, as illustrated by arrow XXII in Fig. 22, the shaft member 70
can swing around the axis of the rotation force transmission pin 95 with respect to
the intermediate member 160.
[0151] In contrast, as is well understood from Figs. 20 and 21(b), the guide member 165
of the intermediate member 160 is arranged at a position where the guide member 165
penetrates the guide member insertion groove 150d, reaches the bottom portion 149
side, and can slide on the guide surfaces 151 and 152. Then, as will be described
later, the guide member 165 slides on the guide surfaces 151 and 152 so that the intermediate
member 160 is guided. As a result, as illustrated by arrow XXIIIa in Fig. 23(a), the
intermediate member 160 can be rotated inside the body 145.
[0152] In addition, as is well understood from Figs. 20, 21(a), and 21(b), the intermediate
member 160 is arranged inside the groove 150b so that the thickness direction of the
intermediate member 160 is the groove width direction of the groove 150b formed in
the holding portion 150. Therefore, a portion of the intermediate member 160 is arranged
inside the groove 150b, and the intermediate member 160 can be moved so as to slide
inside the groove 150b.
[0153] As described above, in the end member 140 of the present embodiment, the intermediate
member 160 is held by the guide surfaces 151 and 152 formed in the body 145 so as
not to slip out, and the shaft member 70 is held by the intermediate member 160 so
as not to slip out. More specifically, the guide member 165 engages with the guide
surfaces 151 and 152 of the body 145, thereby regulating a movement of the shaft member
70 in the direction in which the shaft member 70 is pulled out from the body 145.
[0154] In this manner, the shaft member 70 is not directly held by the body 145. However,
the proximal end portion 90 of the shaft member 70 is configured so that a movement
thereof in directions other than the direction in which the shaft member 70 is pulled
out from the body 145 is regulated by the concave portion 150c (for example, refer
to Fig. 16) formed in the holding portion 150 of the body 145.
[0155] It is possible to adjust a clearance (so-called "slack") between the shaft member
70 and the body 145 by using a relative positional relationship between the guide
surfaces 151 and 152 and the guide member 165 and a dimensional relationship between
the proximal end portion 90 and the concave portion 150c.
[0156] This assembly work of the end member 140 can be carried out by first arranging the
shaft member 70 in the intermediate member 160 and attaching the intermediate member
160 to the body 145. In this case, when the guide member 165 of the intermediate member
160 is caused to penetrate the guide member insertion groove 150d, the assembly work
can be carried out through elastic deformation using a weak force. Therefore, it is
possible to assemble the shaft member 70 to the bearing member 141 easily and with
increased productivity. In addition, not only the assembly work is facilitated, but
also the detachment work is similarly facilitated. Accordingly, the reuse is also
facilitated. Particularly, in this case, it is not necessary to deform the shaft member
70 during the insertion and the detachment. Accordingly, there is no more possibility
of damage. In addition, since the detachment is facilitated, workability can also
be improved.
[0157] As described above, the shaft member 70 is arranged inside the bearing member 141,
thereby enabling the shaft member 70 to swing as illustrated in Figs. 22, 23(a), and
23(b). That is, in a viewpoint illustrated in Fig. 22, the shaft member 70 can swing
around the axis of the rotation force transmission pin 95 as illustrated by arrow
XXII. In contrast, in a viewpoint illustrated in Fig. 23(a), the shaft member 70 can
swing to follow the rotation of the intermediate member 160 as illustrated by arrow
XXIIIa. In this case, as illustrated in Fig. 23(b), the guide member 165 slides on
the guide surfaces 151 and 152. In this manner, the rotation of the intermediate member
160 is guided, and based on this guidance, the shaft member 70 can swing.
[0158] The swing illustrated in Fig. 22 and the swing illustrated in Fig. 23(a) are swings
in a direction in which the swings are orthogonal to each other.
[0159] In addition, when the driving force is received from the apparatus body 10, the shaft
member 70 receives the rotation force acting around the axis as illustrated by arrow
XXc in Figs. 20 and 21(a). In this case, both end portions of the rotation force transmission
pin 95 of the shaft member 70 press the pieces 161a and 162a (refer to Fig. 19(b))
of the intermediate member 160, and the intermediate member 160 is caught on by the
lateral wall of the groove 150b of the body 145. In this manner, the rotation force
can be transmitted to the photosensitive drum 35.
[0160] If the distal end of the rotation force transmission pin 95 extends to reach the
inside of the guide groove 150b of the holding portion 150 of the body 145, even when
the pieces 161a and 162a are not arranged, the distal end of the rotation force transmission
pin 95 is caught on by the lateral wall of the guide groove 150b when rotated. In
this case, the rotation force can be transmitted without pressing the intermediate
member 160.
[0161] According to this end member 140, it is possible to obtain an advantageous effect
which is the same as that according to the above-described end member 40.
[0162] The above-described configuration enables the shaft member 70 to be pivotally moved
(swing), to transmit the rotation force, and to be held by the bearing member 141.
The end member 140 is attached to the photosensitive drum 35 by inserting the end
portion on a side where the shaft member 70 does not protrude within the end member
140 into the photosensitive drum 35 after the end member 140 is assembled as illustrated
in Fig. 14. This end member 140 properly applies the rotation force to the photosensitive
drum 35 when the process cartridge 20 is mounted on the apparatus body 10, and enables
the process cartridge 20 to be easily attached and detached.
[0163] Next, a third embodiment will be described. Fig. 24 is a view for describing the
third embodiment, and is a view illustrating an intermediate member 260. Fig. 24(a)
is a perspective view, Fig. 24(b) is a front view, and Fig. 24(c) is a plan view.
[0164] In the present embodiment, a form of a portion with which the rotation force transmission
pin 95 of the shaft member 70 within the intermediate member 260 is different from
that of the intermediate member 160. Other elements are the same as those of the above-described
end member 140, and thus, the intermediate member 260 will be described here.
[0165] The intermediate member 260 is formed in a semi-annular shape in a front view as
illustrated in Fig. 24(b), and grooves 261 and 262 extending in the radial direction
are formed on an end surface thereof. The groove width of the grooves 261 and 262
is approximately the same as the diameter of the rotation force transmission pin 95.
Then, snap-fit (interference-fit in the entrance portion) structures 261a and 262a
are formed on the end surface side of the intermediate member 260 in the grooves 261
and 262. This enables the rotation force transmission pin 95 of the shaft member 70
to engage with the grooves 261 and 262 without being detached therefrom. Fig. 25 illustrates
a view for describing this configuration.
[0166] Fig. 25(a) is a perspective view illustrating a posture where the shaft member 70
is combined and engaged with the intermediate member 260, and Fig. 25(b) is a cross-sectional
view taken along the axis in Fig. 25(a). As is understood from Figs. 25(a) and 25(b),
at least a portion of both end portions of the rotation force transmission pin 95
is arranged inside the grooves 261 and 262. In addition, a configuration is adopted
so that the snap-fit structures 261a and 262a cause the rotation force transmission
pin 95 not to slip out from the grooves 261 and 262.
[0167] According to this intermediate member 260, it is possible to more easily attach the
shaft member 70 to the intermediate member 260. Therefore, for example, when the photosensitive
drum unit 30 is assembled, the bearing member in which the intermediate member 260
has been already mounted on the body is first fixed to the end portion of the photosensitive
drum 35. Thereafter, the shaft member 70 can be mounted on the intermediate member
260 of the bearing member. According to this assembly, it is possible to attach the
unstably swinging shaft member 70 individually and lastly. Therefore, it is possible
to improve convenience in the assembly.
[0168] In addition, in the snap-fit structures 261a and 262a for regulating the detachment
(disengagement) of the rotation force transmission pin 95 and the snap-fit structures
150e and 150f of the guide member insertion groove 150d for regulating the detachment
(disengagement) of the guide member 165, a degree of a force needed to pull out (disengage)
the rotation force transmission pin 95 and the guide member 165 is adjusted. In this
manner, it is possible to cause the intermediate member to remain in the body side
when the shaft member 70 is detached, and to detach the intermediate member 260 together
with the shaft member 70 from the body. For example, when the body 145 and the intermediate
member 260 are combined for reuse, an interference-fit condition of the snap-fit structures
261a and 262a is adjusted to be relatively weaker than an interference-fit condition
of the snap-fit structures 150e and 150f of the guide member insertion groove 150d,
and it is no longer necessary to separately manage the intermediate member 260 and
the body 145 since the intermediate member 260 remains in the body 145. Therefore,
the reuse is further facilitated, and the workability is improved. On the other hand,
when only the body 145 or only the intermediate member 260 is reused, if the intermediate
member 260 does not remain in the body 145, man-hours are reduced in separating the
intermediate member and the body later. Therefore, the interference-fit condition
of the snap-fit structures 261a and 262a may be adjusted to be relatively stronger
than the interference-fit condition of the snap-fit structures 150e and 150f of the
guide member insertion groove 150d, thereby improving the workability.
[0169] Next, a fourth embodiment will be described. In the fourth embodiment, a form of
a body 345 is different from the form of the above-described body 145. Other elements
can be similarly considered, and thus, the body 345 will be described here. The same
reference numerals are given to those which are considered to be the same as the members
and elements which have been described hitherto, and description thereof will be omitted.
[0170] Fig. 26(a) illustrates a plan view when the body 345 is viewed from a side into which
the intermediate member 160 is inserted, and Fig. 26(b) illustrates a perspective
view of the body 345. In addition, Fig. 27 illustrates a cross-sectional view along
the axis including a line illustrated by XXVII-XXVII in Figs. 26(a) and 26(b). Furthermore,
Fig. 28(a) illustrates a cross-sectional view along the axis including a line illustrated
by XXVIIIa-XXVIIIa in Figs. 26(a), 26(b), and 27. Then, Fig. 28(b) illustrates a cross-sectional
view along the axis including a line illustrated by XXVIIIb-XXVIIIb in Figs. 26(a),
26(b), and 27.
[0171] The bottom portion 149 extending in a rod shape in the radial direction of the cylindrical
body 46 is disposed in a cylindrical inner side of the cylindrical body 46 so as to
close at least a portion of the inner side of the cylindrical body 46. Furthermore,
a holding portion 350 is disposed on an inner side opposite to a side fixed to the
photosensitive drum 35 across the bottom portion 149 within the inner side of the
cylindrical body 46.
[0172] The holding portion 350 forms guide surfaces 351 and 352 serving as an intermediate
member guide on the inner side of the cylindrical body 46. Therefore, the holding
portion 350 is arranged so that two projections 350a protrude from the inner surface
of the cylindrical body 46 toward the axis of the cylindrical body 46 and face each
other. A groove 350b is formed between the two projections 350a.
[0173] A form of the holding portion 350 will be further described in detail.
[0174] As is well understood from Figs. 26(a) and 26(b), the two projections 350a are arranged
to face each other, and a gap is formed therebetween, thereby configuring the groove
350b. In addition, the projection 350a has a concave portion 350c so that a sphere
having the center on the axis of the cylindrical body 46 within the projection 350a
is partially hollowed. A portion of the spherical surface of the concave portion 350c
has a shape which enables the spherical body 90 of the shaft member 70 to be accommodated
therein. However, the concave portion 350c may not necessarily have the spherical
surface.
[0175] Then, guide surfaces 351 and 352 are formed on a surface opposite to the concave
portion 350c within the projection 350a.
[0176] Furthermore, in the holding portion 350, a guide member insertion groove 350d is
disposed between the cylindrical body 46 and the concave portion 350c within the end
surface of the projection 350a. The guide member insertion groove 350d is disposed
so as to cause the concave portion 350c side to communicate with the guide surfaces
351 and 352 side, and further one end thereof is open through the groove 350b. A size
and a shape of the guide member insertion groove 350d are formed so that the guide
member 165 of the intermediate member 160 can be inserted into the guide member insertion
groove 350d.
[0177] In the present embodiment, the guide member insertion grooves 350d are respectively
disposed on one side and the other side of the groove 350b. However, the guide member
insertion grooves 350d are not necessarily disposed on both sides. The guide member
insertion groove 350d may be disposed on any one side. In the above-described body
145, the guide member insertion groove 150d is disposed on the bottom of the concave
portion 150c. However, in the present embodiment, the guide member insertion groove
350d is disposed in the end portion of the groove 350b as described above. This can
eliminate a possibility that the guide member insertion groove 350d influences the
movement of the intermediate member 160. That is, as will be described later, when
the guide member 165 of the intermediate member 160 moves along the guide surfaces
351 and 352 (refer to Fig. 27) of the holding portion 350, the guide member 165 is
not caught on by the guide member insertion groove 350d. Accordingly, a smooth movement
is allowed. In addition, even when the shaft member 70 is pulled carelessly, it is
possible to prevent the shaft member 70 from being detached unintentionally.
[0178] From a viewpoint of manufacturing the end member so that a mold is arranged, it is
also possible to dispose a groove penetrating in the axial direction in any one of
the projections 350a (not illustrated). In this case, the swing of the shaft member
70 is smoothly maintained by forming the groove to be thinner than the guide member
165.
[0179] As described above, a surface is also formed on a side opposite to the concave portion
350c within the projection 350a (that is, a side opposing the bottom portion 149 within
the holding portion 350). As is understood from Fig. 28(b), the surface has an arc
shape. These serve as guide surfaces 351 and 352. The guide surfaces 351 and 352 have
a curved surface formed so as to be curved along the extending direction of the groove
350b. The guide member 165 of the intermediate member 160 slides on the guide surfaces
351 and 352, thereby causing the shaft member 70 to swing similarly as described above.
[0180] Therefore, the guide member insertion groove 350d causes the concave portion 350c
side of the projection 350a and a rear surface (surface on which the guide surfaces
351 and 352 are present) of the holding portion 350 to communicate with each other,
and causes the guide member 165 to reach the guide surfaces 351 and 352.
[0181] It is preferable that the holding portion 350 having this form be further formed
as follows.
[0182] The groove width of the groove 350b is not particularly limited, but it is preferable
that the width be arranged to be approximately the same as the thickness of the intermediate
member 160. This can suppress the looseness of the shaft member 70.
[0183] A shape of the inner surface of the concave portion 350c is not particularly limited
as long as the shape enables the proximal end portion of the shaft member 70 to be
accommodated therein. However, when the proximal end portion of the shaft member 70
is the spherical body 90, it is preferable to provide a curved surface having the
same radius as that of the spherical body 90. This also prevents the looseness of
the shaft member 70.
[0184] It is preferable that the guide member 165 of the intermediate member 160 can be
inserted into the guide member insertion groove 350d, and that the guide member insertion
groove 350d adopt a snap-fit (interference-fit in the entrance portion) structure
with respect to the guide member 165.
[0185] The guide surfaces 351 and 352 are surfaces for determining the swing of the shaft
member 70. Therefore, it is preferable that the guide surfaces 351 and 352 have an
arc shape in a cross section illustrated in Fig. 28(b) from a viewpoint that stable
swing can be obtained. That is, it is preferable that the guide surfaces 351 and 352
have an arc shape around the center of the swing of the shaft member 70. This enables
smooth swing. In addition, in the present embodiment, an arc of the concave portion
350c is also configured to be an arc which belongs to the same circle to which the
guide surfaces 351 and 352 belong.
[0186] Figs. 29 and 30 illustrate a view in which the intermediate member 160 is combined
with the body 345 so as to configure a bearing member 341. Fig. 29 is a perspective
view, Fig. 30(a) is a view illustrated by using the same viewpoint in Fig. 28(a),
and Fig. 30(b) is a view illustrated by using the same viewpoint in Fig. 28(b). Fig.
31 is a view illustrating a state of a movement of the guide member 165 when the intermediate
member 160 is combined with the body 345.
[0187] As is understood from these drawings, in the bearing member 341, the guide member
165 of the intermediate member 160 is arranged at a position where the guide member
165 penetrates the guide member insertion groove 350d, reaches the bottom portion
149 side (sequentially as illustrated by a straight line arrow in Fig. 31), and can
slide on the guide surfaces 351 and 352. Then, similar to the above-described bearing
member 141, the guide member 165 slides on the guide surfaces 351 and 352. In this
manner, the intermediate member 160 is guided. As a result, the intermediate member
160 can be rotated inside the body 345.
[0188] In addition, as is well understood from Fig. 29, the intermediate member 160 is arranged
inside the groove 350b so that the thickness direction of the intermediate member
160 is the groove width direction of the groove 350b formed in the holding portion
350. Therefore, a portion of the intermediate member 160 can be arranged inside the
groove 350b, and the intermediate member 160 can be rotated (swung) so as to slide
inside the groove 350b.
[0189] Furthermore, in the bearing member 341 of the present embodiment, as is well understood
from Figs. 29 and 30(a), when both ends of the intermediate member 160 adopt a posture
of being arrayed side by side in the direction orthogonal to the axis of the body
345 (radial direction of the body 345), the grooves 161 and 162 of the intermediate
member 160 adopt a structure in which the grooves 161 and 162 of the intermediate
member 160 are exposed by projecting from the projection 350a formed in the holding
portion 350 of the body 345. Therefore, in the present embodiment, the shaft member
70 can be attached after the intermediate member 160 is combined with the body 345.
Therefore, it is possible to carry out the assembly work more easily and with increased
productivity. In addition, the detachment work of only the shaft member 70 is also
further facilitated. Accordingly, the reuse is also facilitated. Particularly, in
this case, it is not necessary to deform the shaft member 70 during the insertion
and the detachment. Accordingly, there is no more possibility of damage. In addition,
since the detachment is facilitated, the workability can also be improved.
[0190] As described above, the shaft member 70 is combined with the intermediate member
160 of the bearing member 341 according to the present embodiment, thereby configuring
an end member. Then, even in this end member, the intermediate member 160 is held
by the guide surfaces 351 and 352 formed in the body 345 so as not to slip out, and
the shaft member 70 is held by the intermediate member 160 so as not to slip out.
Therefore, the shaft member 70 is not directly held by the body 345. Then, the end
member in which the shaft member 70 is combined with the bearing member 341 can also
be operated similar to the above-described end member 140.
[0191] Fig. 32 is a cross-sectional view illustrating a scene in which the shaft member
70 is combined with the bearing member 341 and the shaft member 70 is most tilted.
As is understood from Fig. 32, even when the shaft member 70 is tilted, the rotary
shaft 85 of the shaft member 70 comes into contact with the body 345 of the bearing
member 341 before the guide member 165 reaches the guide member insertion groove 350d.
Accordingly, the shaft member 70 is no longer tilted. Therefore, there is no possibility
that the intermediate member 160 slips out from the body 345. In addition, even when
the shaft member 70 is pulled, the guide member 165 cannot reach the guide member
insertion groove 350d. Therefore, unintentional detachment does not occur.
[0192] Then, in a swing range of the shaft member 70, when the guide member 165 of the intermediate
member 160 moves along the guide surfaces 351 and 352, the guide member 165 is not
caught on by the guide member insertion groove 350d. Accordingly, the smooth movement
is allowed.
[0193] Fig. 33 is a view for describing a bearing member 341' having a body 345' according
to a modification example of the body 345. Fig. 33(a) is a perspective view of the
bearing member 341', and Fig. 33(b) is an enlarged view of a portion in Fig. 33(a).
In the present example, when both ends of the intermediate member 160 adopt a posture
of being arrayed side by side in the direction orthogonal to the axis of the body
345' (radial direction of the body 345'), a projection 350a' extends in the direction
along the axis so that even the end portion of the intermediate member 160 is hidden
inside a groove 350b'. However, a portion of the projection 350a' is cut out and a
space 350f is formed so that the shaft member 70 can be engaged with the grooves 161
and 162 of the intermediate member 160. The projection 350a' is formed so as to lead
to the grooves 161 and 162 of the intermediate member 160 from the space 350f.
[0194] Fig. 34 is a view for describing a bearing member 341" having a body 345" according
to another modification example of the body 345. Fig. 34 is a perspective view of
the bearing member 341". In the present example, a space 350f" which is larger than
the space 350f' of the body 345' is formed.
[0195] According to the bodies 345' and 345", the spaces 350f and 350f" ensure that the
shaft member 70 is easily attached and detached, and can increase a contact portion
between the intermediate member 160 and the bodies 345' and 345" on the opposite side
of the spaces 350f and 350f". Therefore, it is possible to disperse a load during
rotation.
[0196] Next, a fifth embodiment will be described. In the fifth embodiment, a holding portion
450 of a body 445 is different from that according to the above-described fourth embodiment,
and a guide member 465 of an intermediate member 460 is different from that according
to the above-described fourth embodiment. Other elements can be similarly considered,
and thus, the body 445 and the intermediate member 460 will be described here by focusing
on elements which are different from those in the fourth embodiment. Then, the same
reference numerals are given to those which are considered to be the same as the members
and elements which have been described hitherto, and description thereof will be omitted.
[0197] Figs. 35(a) and 35(b) illustrate a view for describing the body 445. Fig. 35(a) is
a view illustrated by using the same viewpoint in Fig. 28(a), and Fig. 35(b) is a
view illustrated by using the same viewpoint in Fig. 28(b). In addition, Fig. 36(a)
illustrates a perspective view of the intermediate member 460, Fig. 36(b) illustrates
a front view of the intermediate member 460, and Fig. 36(c) illustrates a plan view
of the intermediate member 460, respectively.
[0198] As is understood from Figs. 35(a) and 35(b), similar to the holding portion 350,
the guide member insertion groove 350d is also disposed in the holding portion 450
included in the body 445. In the holding portion 450, a return piece 450e extending
to the guide surfaces 351 and 352 side (bottom portion 149 side) is arranged from
an edge continuous with the guide surface 351 within an edge of the guide member insertion
groove 350d. This causes an internal corner portion 450f which is open to the guide
surfaces 351 and 352 side to be formed between the return piece 450e and the guide
surfaces 351 and 352. Then, the internal corner portion 450f does not appear when
the guide member insertion groove 350d is viewed from the concave portion 350c side.
[0199] In contrast, as is understood from Figs. 36(a) to 36(c), a guide member 465 (guided
portion) whose shape is different from that in the intermediate member 160 is disposed
in the intermediate member 460. That is, in the present embodiment, the guide member
465 has a substantially triangular column shape, and a distal end thereof is tapered
in a cone shape.
[0200] Therefore, projections 465b having apexes of a triangle in both ends of a surface
465a in contact with the guide surfaces 351 and 352 of the holding portion 450 are
formed in the guide member 465.
[0201] According to the above-described configuration, the intermediate member 460 is further
less likely to slip out from the body 445 after the intermediate member 460 is combined
with the body 445. Fig. 37 illustrates a view for the description. Fig. 37(a) illustrates
a cross-sectional view of a scene where the intermediate member 460 is combined with
the body 445, and Fig. 37(b) illustrates a cross-sectional view of a scene where swing
of the shaft member 70 causes the intermediate member 460 to swing together, respectively.
[0202] First, a scene is considered where the intermediate member 460 is attached to the
body 445. In the scene, as illustrated by arrow XXXVIa in Fig. 37(a), the guide member
465 of the intermediate member 460 is arranged on the guide surfaces 351 and 352 side
by penetrating the guide member insertion groove 350d from the concave portion 350c
side. In this case, as described above, the return piece 450e causes the internal
corner portion 450f to be oriented so as not to interfere with the insertion of the
guide member 465. Therefore, the intermediate member 460 can be attached to the body
445 smoothly as usual.
[0203] Next, a scene is considered where the shaft member 70 and the intermediate member
460 swing after the intermediate member 460 and the shaft member 70 are attached to
the body 445. In the scene, as illustrated by arrow XXXVIIb in Fig. 37(b), the guide
member 465 of the intermediate member 460 is guided and moved by the guide surface
351 of the body 445. In this case, if the swing becomes large and the guide member
465 reaches the return piece 450e, the projection 465b of the guide member 465 enters
the internal corner portion 450f formed by the guide surfaces 351 and 352 and the
return piece 450e. Therefore, the guide member 465 can no longer move. Accordingly,
there is no possibility that the guide member 465 slips out from the guide member
insertion groove 350d.
[0204] As described above, according to the present embodiment, there is provided a function
as the above-described end member. The attachment work between the intermediate member
460 and the body 445 can be smoothly carried out. Furthermore, it is possible to more
reliably prevent the intermediate member 460 from slipping out from the body 445 unintentionally.
For example, even when the body 445 and the intermediate member 460 are transported
in an assemble state, there is no possibility that vibrations generated during the
transport cause the intermediate member 460 to slip out therefrom.
[0205] In the present embodiment, the guide member 465 of the intermediate member 460 is
configured to have the triangular column shape as described above, thereby showing
a shape in which the guide member 465 is likely to enter the internal corner portion
450f. However, the shape of the guide member is not particularly limited as long as
the shape of the guide member regulates the movement (rotation) by the guide member
entering the internal corner portion.
[0206] Hitherto, embodiments and examples have been described in which all the described
end members are arranged in the end portion of the photosensitive drum 35 and the
photosensitive drum unit is formed according to this configuration. In contrast, as
described with reference to Fig. 2, the process cartridge additionally includes the
developing roller unit having the columnar rotary body or the charging roller unit.
Therefore, all the end members according to the above-described embodiments and modification
examples can be applied to the developing roller unit or the charging roller unit,
instead of being arranged in the photosensitive drum. In this manner, the developing
roller unit or the charging roller unit can receive the rotation driving force from
the apparatus body. As one embodiment, Fig. 38 illustrates a developing roller unit
523 including the end member 40. Fig. 38 also illustrates a perspective view of the
developing roller unit 523 and a photosensitive drum unit 530 which is arranged to
be adjacent thereto.
[0207] The developing roller unit 523 includes a developing roller 524, a spacer ring 525,
a lid member 526, a magnetic roller (not illustrated), and the end member 40. The
end member 40 is configured as described above. In addition, those which are known
can be applied to other members, but other members include the following configurations,
for example.
[0208] The developing roller 524 is a member in which an outer peripheral surface of a columnar
rotary body is coated with a developer layer. In the present embodiment, the developing
roller 524 is a conductive cylinder made of aluminum, and is configured so that a
material configuring the developer layer is applied thereto.
[0209] The spacer ring 525 is an annular member which is arranged so as to wind around each
outer peripheral surface in both ends of the developing roller 524, thereby holding
a constant gap between the developing roller 524 and the photosensitive drum 35. The
thickness of the spacer ring 525 is approximately 200 µm to 400 µm.
[0210] Similar to the above-described lid member 36, the lid member 526 is a bearing which
is arranged on one end side of the developing roller 524, and which causes the developing
roller 524 to be rotated around the axis in one end of the developing roller unit
523.
[0211] The magnetic roller is arranged inside the developing roller 524, and thus is not
illustrated in Fig. 38. However, the magnetic roller is a roller formed of a magnetic
material or a resin containing the magnetic material, and multiple magnetic poles
are arranged along the axis. In this manner, it is possible to deposit a developer
on a surface of the developing roller 524 by using a magnetic force.
[0212] The end member 40 is configured as described above, but is arranged in an end portion
opposite to the end portion in which the lid member 526 is arranged within the end
portion of the developing roller 524. Herein, an example of applying the end member
40 has been described. However, without being limited thereto, any other end member
already described above can also be applied.
[0213] In this case, for example, the photosensitive drum unit 530 can be configured as
follows. That is, the photosensitive drum unit 530 includes the photosensitive drum
35, and lid members 36 and 540 which serve as a bearing for rotating the photosensitive
drum 35 around the axis in each portion of both ends of the photosensitive drum 35.
In this case, one lid member 540 includes a gear portion 541 which meshes with a gear
48 of the end member 40 arranged in the developing roller unit 523 and receives the
rotation force.
[0214] As described above, each end member may be a configuring member included in the developing
roller unit. In this case, the end member is also operated similarly to when included
in the photosensitive drum unit.
Industrial Applicability
[0216] According to the present invention, there are provided a bearing member, an end member,
a photosensitive drum unit, a developing roller unit, a process cartridge, an intermediate
member, and a bearing member body which ensure sufficiently smooth swing of a shaft
member.
Reference Signs List
[0217]
- 10:
- image forming apparatus body
- 20:
- process cartridge
- 30:
- photosensitive drum unit
- 35:
- photosensitive drum (columnar rotary body)
- 40, 140:
- end member
- 41, 141:
- bearing member
- 45, 145, 345, 445:
- body
- 50, 150, 350, 450:
- holding unit
- 60, 160, 260, 460:
- intermediate member
- 70:
- shaft member
- 523:
- developing roller unit
- 524:
- developing roller (columnar rotary body)